Determination of prostaglandin F2alpha and E2 contents in human cerebrospinal fluid by the radioisotope dilution method

Prostaglandin F2alpha and E2 contents in human cerebrospinal fluid were determined by the radioisotope dilution method. The mean values of PGF2alpha and PGE2 of men were 9.8+/-0.87 ng/ml and 6.5+/-1.39 ng/ml, respectively. Those of women were 8.3+/-1.4 ng/ml and 6.9+/-1.72 ng/ml, respectively. The correlation between age and PG was significantly with PGE2 of men and with PGF2alpha of women.

[Influence of denervation on metabolism of phospholipid in the rat vas deferens]

Influence of denervation on phospholipid metabolism in the vas deferens and effect of phospholipase C treatment on sensitivity of the vas deferens for noradrenaline were studied. The incorporation of 32P-orthophosphate into phosphatidylethanolamine and phosphatidylcholine was markedly increased by denervation. Incorporation of 32P-orthophosphate into proteolipid was accelerated more than that of 3H-leucine. Sensitivity of the denervated vas deferens for noradrenaline was strongly reduced by phospholipase C treatment. These data suggest that the supersensitivity of the denervated vas deferens for noradrenaline was mainly due to the increase in phospholipids.

[Biological assay of prostaglandin using the rat uterus]

Isometric contraction of rat uterus with PGF2alpha was more reliable and stable than when a stomach preparation was used. The method of PG bioassay using rat uterus was as follows: ovariectomized rats were given 10 mug of estrone s.c. 48 hr before the decapitation. Uterine strips were suspended in 2 ml of organ bath containing modified Locke-Ringer solution at 25 degrees C, and the isometric contraction was determined. As little as 4 ng/ml of PGF2alpha was determined quantitatively with this method.

Sex difference in the development of fatty liver by orotic acid

Effects of orotic acid on liver lipid accumulation and incorporation of methionine [methyl-14C] into liver phosphatidylcholine and protein, and into serum beta-lipoprotein were studied. Male and female rats of Wistar strain were fed a semisynthetic diet supplemented with 1 per cent orotic acid for 7 days. Feeding of orotic acid induced a marked fatty liver in female rats, but not in males. In female rats, radioactivity in liver phosphatidylcholine was significantly decreased by orotic acid, and that in liver protein was slightly decreased. In male rats, incorporation of methionine [methyl-14C] into liver phosphatidylcholine and protein was unchanged between the control and the rats fed orotic acid. Radioactivity in serum beta-lipoprotein was decreased to a greater extent in female rats than in males. These results suggest that sex difference in the development of fatty liver may be due to the difference in the effect of orotic acid on liver phosphatidylcholine biosynthesis.